What filter size does the sigma 50 120mm f 2 8 dc os contemporary take?

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From Sigma 50-120mm f/2.8 DC OS Contemporary: Sigma 50-120mm f/2.8 DC OS Contemporary: A zoom lens by Sigma for APS-C cameras, 50-120mm f/2.8. A compact constant f/2.8 telephoto zoom for APS-C, about 75-180mm equivalent. Specs - Maker: Sigma - Focal length: 50-120mm (zoom) - Maximum aperture: f/2.8 - Made for: APS-C sensors - Mounts: Sony E, Fujifilm X, Canon RF - Stabilised: yes - Autofocus: yes What it frames like - On APS-C (Sony E, Fujifilm X): like 75-180mm on full frame; f/2.8 ...

From Sigma 17-70mm f/2.8-4 DC Macro OS HSM Contemporary: Sigma 17-70mm f/2.8-4 DC Macro OS HSM Contemporary: A macro lens by Sigma for APS-C cameras, 17-70mm f/2.8-4. The Pentax version has no optical stabilisation and relies on the camera's in-body stabilisation.

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